She doesn't look back. There's only one person Morrigan looks over her shoulder for and it isn't ever someone she happens to be with, just the spectre that everyeone has lying in wait for them. If there was more time. If she and Alistair, Zevran and Leliana, if all of them had their heads together but that's more people and even if she does trust them with the secret how does it help? More people who might point out a thing she's overlooked? (Another reminder that ultimately he was a selfish act or the result of it, that the day Kieran learns the truth of how he came to be and if he hates her for it that she will only ever have herself to blame.)

Too many of the Wardens have made spectacularly bad decisions. Too many people outside the Wardens have very real reasons to be uneasy with them. Too many people sit and wonder at what Corypheus is and what this all means.

"You are no use to anyone dead Alistair," she replies, though the sentiment is appreciated nonetheless. When it comes down to it if she's being cold and hard and pragmatic, he's the most use to her alive but how many people can she actually trust to any degree here? "Perhaps keep Zevran's collection of rogues close to you if you ever have a reason to fear then. Kirkwall...of all places. I had thought Haven the most spectacularly poor choice to be made and that at least could be blamed upon the Chantry. The Veil is so thin there Alistair. That, red lyrium? Not so far from Vimmark..." Hopefully Alistair understands the last part isn't solely about Kieran; she'd rather not have some runner reporting to someone that she was questioning a Warden about Corypheus' hold on the Wardens.

But she did go to Vimmark after all.